Role of Potato in Human Health

–Colloquesurlapommedeterre2011 1

RoleofPotatoinHumanHealth

DanielleDonnelly,Ph.D.&StanKubow,Ph.D.PlantScienceDept.&SchoolofDieteticsandHumanNutrition

McGillUniversity,MontrealINTRODUCTIONPotatohasbeenusedasafoodforhumansformorethan10,000years,startinginSouthAmericawhere itoriginated. IntheAndesMountains,youcanstill findpotatopreparedaschuῇotoday. Inthisprocess,tubersarepiledonthegroundandrepeatedlyfrozenoverseveralnights.Skinremovalis done by trampling, then soaking or leaching in river water removes the bitter flavors ofglycoalkaloids.Finally,sun‐dryingpreserveschuῇoforuptoseveralyears.Anotherdryproductispapaseca,whichisproducedbyboiling,peeling,slicing,sun‐dryingandthengrinding.Bothchuῇoandpapasecaareusedinstewsandsoups.Inthe1500’spotatowerespreadtoEuropeancountries,including Spain and England. Early consumers, including sailors, may have benefited from therelatively high vitamin C content of potato, which helped to prevent scurvy. Potato became sowidely distributed in Europe that it is often called the “Irish potato” or “European potato”.Nowadays, potato are grown in 160 countries and eaten fresh or following storage in mostcountries. In some countrieswhere people have insufficient food, improved potato cultivars thatdeliver more nutrients, or better potato preparation and processing to increase micronutrientavailability, is needed. In some countrieswhere food iswidely available, as in Canada, consumerdemand is for food that ismore convenient to eat, better tasting or novel, andhealthier, such asorganically‐grownproduceorcultivarswithgreatervitaminormineralcomposition.Inmany countries of theworld, humans are getting heavier, and succumbing to awide range ofmetabolicdisorders thataccompanyoverweight andobesity.Althoughmany factorsare toblameforthis,includinggeneticsandsedentarylifestyle,carbohydrate‐richfoodssuchaspotatoareoftenblamed.On theotherhand,potatohasan importantnutritional role toplay inareasof theworldwheretheyareanimportantstaplecrop–fortheirgreatnutritionalvalue.Thefollowingpagesoutline: Wherepotatoisgrownandeaten Potatonutritionalvalueandhealthproperties RoleofpotatoindiseasepreventionWORLDPOTATOGROWINGAREASPotato has tremendous yields per unit area compared with many other food crops. Yields aregreatest in North America (averaging 40.6 tha‐1), where they are double that of Europe, LatinAmerica,orAsia,andmuchgreaterthaninAfrica.This isduetothecoolNorthAmericanclimate,

–Colloquesurlapommedeterre20112

amplerainfall,mechanizationandeconomiesofscale,relativelyhighinputs,longergrowingseasonforwhichthelongerseason,higheryieldingcultivarsaresuited,andbetterproductionsystemsthatrotatecerealsandforageswithpotato;thesediscouragediseaseandimprovesoilstructure.Whilepotatogrowingareashavedeclinedoverthepast20yearsinNorthAmerica,Europe,andtheformerSovietUnion,growingareashavedoubledindevelopingareasthatincludeAfrica,Asia,andLatinAmerica.The top threeworld leaders inpotatoproductionareChina (#1) and India (#3),bothwithasteeptrajectoryforincreasingpotatogrowingareasofaround6%perannum,andtheRussianFederation(#2).Asianproductionisincreasingsorapidlybecauseofincreasingnumbersof potato consumers in both areas of production and non‐production, increasing interest inprocessed potatoes, and use as animal feed for an expanding livestock industry. Half the globalpotatosupplyisnoweateninAsia.Therelativelylowpercapitaconsumptionindicateslotsofroomforincreaseddemand,whichcoulddoubleortripleinthenextfewyears.RecentsoaringfoodpricesinAsiaandAfricaresultedfromdiversionofgrainfromanimalfeedtobiofuels,aswellasshortagesof fuel and fertilizers. Potato is increasingly important to world food security in developingcountries,whereitsupplementsorhasreplacedgrain‐baseddiets.Global climate change is already impacting agricultural production. Major adaptions will involveplanting time and cultivar choices (particularly more heat tolerant cultivars) and will vary withgeographicareas.Leastaffectedwillbehighlatitudes(Canada,China,Russia,Scandinavia)andhighaltitudes in the tropics (AltiplanoofPeruandBolivia)whereproductionareamay increase.Mostaffectedareaswillbelowerlatitudes(Europe,Russia,andKazakhstan)whereyieldispredictedtodeclineandsubtropicalareas(India,Bangladesh)wherepotatoisalreadygrownduringthecoolestseasonofferinglittlescopetomaintaingrowingareaandyields.POTATONUTRITIONALVALUE&HEALTHPROPERTIESPotatoishigherindrymassandproteinperunitgrowingareathancereals!However,consumersareoftenunder the impression that potatoesmakeyou fat; that they arehigh in calories and fatcomparedwithothercarbohydratesourcessuchasrice,pasta,orbread.Thisisincorrectaspotatohas negligible fat and a low energydensity similar to legumes. Potato andpotato products couldreplacecerealorcerealproductsinmanycookedandprocessedfooditems.CarbohydratesCarbohydrates, primarily starch,make up 10‐30% of the total freshmass of the tuber. The latermaturing cultivars achieve the largest size and greatest starch yield compared with the earliermaturingcultivars.Starchispackedintostarchgranulesthatcontaintwoformsofstarch;amylose(long chains of glucose residues) and amylopectin (branched chains of glucose residues). Onaverage, cultivated potato have a ratio of about 1 : 3 amylose : amylopectin.However, the rangeamong cultivars is 22‐43% amylose. It is generally agreed that cultivars with greater amylosecontent would be healthier. One reason for this relates to the speed at which potato starch isdigestedtosugarswhichenterthebloodstream.Thecrystal‐likepropertiesofstarchgranulesmakethemresistanttostarch‐digestingenzymes,withamylosemoreresistanttoenzymaticcleavagethanamylopectin. The cooking process causes starch to gelatinize and loose its crystalline properties.

–Colloquesurlapommedeterre2011 3

Thismakes the starchmore readily solubilized. From thehumanhealth point of view amylose ismoreresistanttodigestionthanamylopectin.Whenweeatstarcheswithrelativelygreateramylosecontent,thedigestionisslowedsothebloodglucoseraisingresponseislowerthanwhenamylosecontent is less. When potato is cooked and then cooled, as when potato salad is made, starchretrogrades(resumesitscrystallineproperties).Potatosaladisthereforeahealthierproductthanhotboiledormashedpotato(dependinguponwhatyoueatitwith).Potatothatisfriedinoiltendsto absorb less fat if the starch content is greater in amylose than amylopectin as the strong film‐forming characteristics of amylose are known to inhibit oil pick‐up in fried foods. Since higheramylosestarchesreduceoilpenetrationtheyarefavoredforuseinsnackfoodstoreduceconsumerfatintake.Asastarchitem,potatoshouldbeconsumedinmoderationandwithoutexcesslipidadditions.Itisnotnecessarytorestrictpotatofromthedietsofpeopleattemptingweightcontrolorweightloss.Inaddition to the important food benefits of the potato, a meal containing potato contributes to afeelingoffullness(satiety).Thisisagoodthinginpreventingover‐eating.Potatoservingsdonotinthemselves promote overweight or obesity; this is a complex problem with many contributingfactors,particularlyinactivityandconsumptionofstarchyfoodwithadditionsofhighcalorielipids.Instorage, theequilibriumbetweenstarchand theirsugarbreak‐downproductscanchangewithtime.Themoresugarsarepresent,thedarkerthefrycolourasthesesugarscaramelizeinthehotoil.Quebecerslovetheirdark‐colouredFrenchfries!However,theindustryforfrozenfryproductsisgearedtowardsaverypaleproduct.Whyisthis?Whencarbohydrate‐richfoodisheated,reducingsugarsandtheaminoacidasparaginecancombineto formatoxicproductcalledacrylamide.Theamountofacrylamidepresentinsomecommonlyeatenfoods,suchastoast,coffee,andFrenchfriesisworrying.Itappearsprudenttolimitacrylamideinheatprocessedpotatoproducts,althoughnostudieshaveyetsupporteda linkbetweendietaryacrylamideexposureandhumanneurotoxicity.Thishasbeenrelated inpart tohumanexposures todietaryacrylamidebeing from50‐300 timeslowerthan inanimalexperimental toxicitystudies.Moreover,sinceacrylamide is found inawidevarietyofregularlyconsumedfoods, largechanges inacrylamideconcentrationeither forasinglefoodorcategoriesoffoodsisunlikelytoimpactsignificantlyonoverallintakeorhealthriskforthepopulation.Theadvice fromtheUSFoodandDrugAdministration is toeatabalancedandvarieddietlowintransandsaturatedfatandrichinwholegrains,fruits,andvegetables.ProteinPotato protein generally ranges from 1‐1.5% of tuber fresh mass. Compared with other rawvegetables,potatoisnottypicallythoughtofasagooddietaryproteinsource.However,thequalityofpotatoproteinisexceptionallygood.Onascaleofbiologicalvalue(BV)comparedtowholeegg(BV100),potatohadaBVof90‐100.Incontrast,soybeanwas84andbeans73.Comparedwiththecereal proteins, potato has more lysine and less sulfur‐containing amino acids (methionine andcysteine). Patatin is themajor storage protein, but there are others of importance. One of these,proteinase inhibitor2,hasbeen incorporated intoaweight losssupplement(Slendesta®)as thisproteinactsasanappetitesuppressanttoincreasesatiety.

–Colloquesurlapommedeterre20114

Atvariouspointsinhistory,suchasinEuropeatthetimeofthe“PotatoFamine”peoplewereabletosustain themselvesonadietofpotatoalone,orwith fewotherdietary items, suchas cow’smilk.Thereareindividualstodaywhosubsistonadietofpotatoalone,sometimesforaverylongtime,without apparent illness. This is largely attributed to the high energetic value of potatocarbohydratesincombinationwiththehighqualityofpotatoprotein.

LipidsandDietaryFibreOnlyatinyfractionofpotatoweight(0.15g/150gFM)iscomposedoflipids;lessthancookedrice(1.95g)orpasta(0.5g).Thedietaryfiberissuppliedbycellwalls,particularlythethickcellwallsofthepeel(periderm)whichmakesup1‐2%ofthetuber.Thesefibersarebelievedtoplayadietaryroleinreducingcholesterollevels.Thisisoneverygoodreasontoeatyourpotatopeels! MineralsMinerals are important to maintaining health through their function as electrolytes, enzymeconstituents,antioxidants,andstructuralcomponentsforbonesandteeth.Mineraldeficienciesarecommonaroundtheworldbecauseof therelatively lowcontentofbioavailableminerals inmanystaplecrops.Globally,calcium,iron,selenium,iodine,andzincdeficienciesarethemostwidespreadforms ofmineralmalnutrition. Depending on the age range and gender, many Canadians do notappear to bemeeting their dietary needs for calcium,magnesium, phosphorus, zinc, copper, andiron.

Arecentstudydoneinourlab,withhelpfromlocal industry,comparedthemineralcontentof16cultivarsgrownat5sitesinCanada.TheQuebecsitegrew‘Chieftain’,‘Goldrush’,‘RussetBurbank’,and ‘YukonGold’.Wedetermined that a consumerwho eats one serving of potato per day couldreceive from 30‐48% of the recommended daily intake (%RDI) for macrominerals except forcalcium and sodium and from 6‐82% of the RDI for trace minerals. Across all 5 growing sites,‘RussetBurbank’‘Freedom’and‘YukonGold’hadthegreatestcontributionofmineralsperserving(150g freshmass). In one serving aday, these supply30‐62%of theRDI for themacromineralsmagnesium,phosphorusandpotassium(twice theoverallaverage)and12‐82%of theRDIof thetracemineralscopper,iron,selenium,andzinc(1.3‐3.4timestheoverallaverage).

Sopotato,asamajorstaplefoodcrop,couldplayanimportantroletocombatmineraldeficienciesthroughitsrelativelyhighmineralcontent.Also,potatoishighincompoundsthatpromotemineralbioavailability, such as ascorbate, β‐carotene, organic acids, and cysteine‐rich polypeptides.Furthermore,potatoisrelativelylowinanti‐nutrientsthatdecreasemineralbioavailability,suchasoxalatesandphytates.

This studyhighlighted thevery important contributionofpotato to theCanadiandiet in termsofmineral content, particularly due to the substantial estimated consumption of potatoes in theCanadian diet (190.66 g/person/day); more than one serving. It also showed that some potatocontribute more minerals than others, so using cultivar names would help consumers requestspecific high‐mineral cultivars. On a cautionary note, none of the potato examined were high incalcium, and many Canadians are deficient in this mineral. A potato with a significantly greatercalciumcontentwouldbedesirable.

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VitaminsandOtherUsefulPhytochemicalsPotatoes are an important sourceof vitaminC (ascorbic acid) inmany areasof theworld. Levelsrange from 84‐145 mg per 100 g dry mass, depending on cultivar, planting site, and storageconditions.VitaminC is importanttotheavailabilityof iron,amineral thattendstobe limiting inourdiet.AlsopresentareseveralBvitamins(folicacid,niacin,pyridoxine,riboflavin,andthiamin).Inparticular,potatoesaredescribedasagooddietarysourceofpyridoxine(vitaminB6).Carotenoids,andtheirderivativexanthophyllsarediverselipid‐solublepigments.Xanthophyllsarethe most abundant carotenoids in potato. Two of these pigments (β‐carotene and lutein) areimportantineyehealth.VitaminAdeficiencyiswidespreadglobally.Thisleadstovariousailments,includingblindnessandprematuredeath.β‐carotene isapotentdietarysourceofvitaminA(pro‐vitaminA).Lutein isanoxygenatedxanthophyll thatprotectsagainstoneof the leadingcausesofvisual impairment and blindness in older North American adults, called macular degeneration.Yellow‐fleshed potatoes are the best source of lutein,with a trace of β‐carotene. However, you’dhavetoeatalotofyellowpotatotomeetyourβ‐caroteneandluteinrequirementsformaximumeyehealth. It is best to supplementwith root vegetables such as carrot and sweet potato, aswell asbrightlycolouredfruitincludingbellpepperandtomato.ROLEOFPOTATOINDISEASEPREVENTIONAsnotedabove,potatocontainsenergy‐richcarbohydrates,high‐valueprotein,islowinfats,andisimportantasasourceofvitaminsandminerals.Assuch,potatohasanimportantroleinmaintainingourhealth.Potatoesalsocontainadiversenumberofcompounds,includingvitaminC,carotenoids,someminerals,andvariousphenolicsubstancesthatareimportantasantioxidants.Most antioxidants are invisible to us, including phenolic acids and polyphenols that occur inrelativelyhighconcentrationanddiversityinpotatotubers.Theseincludechlorogenicacid,caffeicacid, ferulic acid, and others. Polyphenolic compounds are responsible for a large part of theantioxidant capacity of potatoes. Other antioxidants are pigments that are highly visible, andbrightlycoloured,suchasanthocyaninsandcarotenoids.Usuallycultivarshighinanthocyaninsarelowincarotenoids,andviceversa,butbreedingeffortsmayovercomethis.Anthocyaninsoccurasred, blue, and purple pigments in skin and flesh ofmanywild species and some cultivars. ThesehighlycolouredpotatoesaremorewidelygrowninCanadanowthaninpreviousyears.Someareforuseincookingorprocessedintochips.Antioxidants are compounds that protect cells and tissues from the damaging effects of reactiveoxygen species (ROS). TheseROS are linked to the initiation and progression ofmany importantage‐related and inflammatory disease conditions, including arthritis, atherosclerosis, cancers,cardiovascular diseases, diabetes, gastrointestinal disorders, and neurodegenerative diseases.Consumption of foods high in antioxidant content is expected to increase antioxidant levels inthe body. Studies have repeatedly shown that people who eat more servings of fresh fruit andvegetables have reduced incidence of awide range ofmetabolic diseases. There is no consensuson the role of vegetable consumption in prevention of cancer. Little has been published onthe long‐term cancer related health effects of potato in diets of consumers around the world.

–Colloquesurlapommedeterre20116

However, short term studies have implicated potato anthocyanins, glycoalkaloids, and lectins asanti‐tumor agents. Little has been published on the role of potato in preventing cardiovasculardisease. It is known that for maximum heart health, potato should be prepared with few fatadditionsandthepeelsshouldbeeatenfortheirfibercontent.Thereissomeevidencethatpotatoprotein,resistantstarch,andphosphorylatedstarchcontributetocholesterol‐loweringproperties.Phytochemicals, particularly antioxidants, are implicated in reducing inflammation, a risk forcardiovasculardisease.Diabetesisincreasingworld‐wideandischaracterizedbyinsulinresistanceand often associated with obesity. The combination within potato of readily absorbablecarbohydrate that rapidly raises blood glucose versus anti‐diabetic factors such as antioxidantscomplicates the role of potato in prevention and management of diabetes. Some antioxidantsincreaseinsulinsensitivity,whichcanbeimportant indiabetesprevention.Twophenolics(caffeicand chlorogenic acids) found in high concentrations in potato, were implicated in prevention oftype‐2diabetes(Paynteretal.,2006)butmorestudiesareneedtoconfirmthelinkbetweenpotatodietaryfiberandpolyphenoliccontentinpreventionormanagementofdiabetes.Thissummarywasabstractedfromthefollowing:Camire, M.E., S. Kubow and D.J. Donnelly. 2009. Potatoes and Human Health. Critical Reviews in

FoodScienceandNutrition.49:823‐840.Nassar, A.M.K., K. Sabally, S. Kubow, Y.N. Leclerc and D.J. Donnelly. 2012. Some Canadian‐Grown

Potato Cultivars Contribute to a Substantial Content of Essential DietaryMinerals. Journal ofAgriculturalandFoodChemistry.60:4688−4696.

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D A N I E L L E   D O N N E L L Y   P L A N T   S C I E N C E   D E P A R T M E N TS T A N   K U B O W   S C H O O L   O F   D I E T E T I C S   &   H U M A N   N U T R I T I O N

M C G I L L   U N I V E R S I T Y   – C R A A Q   N O V   2 3 ,   2 0 1 2

RÔLE DE LA POMME DE TERRE EN SANTÉ HUMAINE

ROLE OF POTATO IN HUMAN HEALTH

ESPÈCES SAUVAGES DE POMMES DE TERRE COMME ALIMENTWILD POTATO SPECIES AS FOOD

• Potato originated in the Andes Mountains of South America, > 10,000 years ago.

• Tremendous genetic variation at the center of diversity.

• Wild species – small tubers, bitter tasting and full of toxic glycoalkaloids.

• Early consumers had to learn to safely prepare these.

• Chuῆo, papa seca are two potato products used in soups and stews even today.

http://nissa.ger‐nis.com/2010/10/07/peruvian‐potatoes‐indigenous‐varietals/

Chuno Papa seca

Reader, 2009. Untold History of the Potato.

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POMME DE TERRE VA VERS L'EUROPEPOTATO GOES TO EUROPE

• Pizarro’s armies conquered the Inca civilization in the 1500’s. 

• Potato fed the Spanish armada and the captive Inca minors who dug for gold, silver, and cinnabar. 

• Potato sustained the Peruvian exploitation by the Spanish who sent gold and silver by the hundreds of tons back to Spain each year for decades.

• Potato, with its high vitamin C content improved the lives of sailors by preventing scurvy.

Pizarro in Lima 1535

Peruvian potato farmers

POMME DE TERRE UNE PLANTE DOMESTIQUÉEPOTATO AS A DOMESTICATED CROP

• Potato became widely distributed in Europe by the 1700’s.

• Early breeders improved tuber size, taste, and safety.

• Today potato is grown in 160 countries and eaten all over the world.

• Cultivated tubers are huge compared to their wild relatives, with better taste, and low glycoalkaloids levels.

• Eaten in a plethora of recipes from fresh or stored potato.

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POMMES DE TERRE EN CULTUREPOTATO AS A STAPLE CROP

• As a staple crop, even small changes in nutrient composition could impact population health.

• Where food is scarce, better cultivars could deliver more nutrients, or better preparation and processing could increase micronutrient bioavailability.

• Where food is plentiful (Canada) consumers want: convenience, taste, novelty, healthier product (organically grown, greater mineral or vitamin composition).

VALEUR NUTRITIVE DES POMMES DE TERRE POTATO NUTRITIONAL VALUE

• Potato is higher in dry mass and protein per unit growing area than cereals!

• Consumers often think that potatoes make you fat; that they are higher in calories and fat than other carbohydrate sources such as rice, pasta or breakfast cereal. Not true! 

• Potato has almost no fat and an energy density similar to legumes. 

• Potato and potato products could replace cereal or cereal products in many cooked and processed food items.

Camire et al., 2009. Critical Reviews in Food Science and Nutrition 49:823-840.

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LES GLUCIDESCARBOHYDRATES

• 10‐30% of tuber fresh mass is starch.

• Starch is made of:Amylose – long chains of glucose residues (resistant starch)

Amylopectin – branched chains of glucose residues

Amylose :Amylopectin average  1:3(33%:66%)

• Potato cultivars contain from 22‐43% amylose.

• Foods with low Glycemic Index have high amylose content.

Amylopectin

MCGILLRECHERCHE SUR L'AMIDON RÉSISTANTRESEARCH ON RESISTANT STARCH

• Higher amylose starches are healthier:

• Starch digestion slowed

• Consumer fat intake less in fried foods

• Our McGill lab is currently working to identify cultivars and parental breeding lines with greater % amylose.

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CUISSON L'AMIDONCOOKING CARBOHYDRATES

• Cooking causes starch to gelatinize = loses its crystal‐like properties that resists digestion.

• When potato is cooked and then cooled starch resumes its crystal‐like properties and becomes a healthier food item (unless fatty dressing is added).

• Acrylamide is found in foods with high carbohydrate content that are heated (toast, coffee, fries).

SATIÉTÉ ET PRÉVENTION DE LA SURCONSOMMATIONSATIETY AND PREVENTION OF OVER‐EATING

• Potato contributes to satiety, the feeling of fullness that you get from eating.

• This is a good thing in preventing over‐eating.

• In a healthy diet, potato should be consumed in moderation and without excess lipid additions. 

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PROTÉINEPROTEIN

• Potato protein ranges from 1‐1.5% of tuber fresh mass.

• High protein quality on scale of biological value (BV) • whole egg (BV 100), • potato is 90‐100, • soybean 84 

• Major storage protein is patatin.

• Another, is proteinase inhibitor 2, ingredient of a weight loss supplement (Slendesta®) used as an appetite suppressant to increase satiety.

patatin

POUVEZ UNE PERSONNE VIVRE SEULE CONSOMMATION DE POMMES DE TERRE ?

CAN A PERSON LIVE ON POTATO ALONE?

• At various points in history, such as in Europe at the time of the “Potato Famine”people were forced to live on potato alone, or with a few other dietary items such as cow’s milk.

• With excellent protein and sufficient energy source, potato can sustain health.

Chris Voigt challenged himself to live on a potato‐only diet for 60 days. He's cooked them every way but no butter, sour cream or any of the usual high‐calorie toppings. Voigt, Exec. Dir. Washington Potato Commission, wanted to make a point about the humble spud's rich nutrients. He ate  20 potatoes a day, or 1,200 potatoes (400 pounds). He stayed healthy and actually lost weight.

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LIPIDES ET FIBRES ALIMENTAIRESLIPIDS & DIETARY FIBER

• Only a tiny fraction of potato weight (0.15 g/150 g FM) is lipids.• < cooked rice (1.95 g) or pasta (0.5 g).

• Dietary fiber is in the cell walls of peel, which makes up 1‐2% of the tuber. • These dietary fibers have an important role in preventing intestinal diseases.

• Eat your potato peels!

MCGILL RECHERCHE SUR MINÉRAUX CHEZ LES CULTIVARS DE POMMES DE TERRE CULTIVÉES AU CANADA

MCGILL RESEARCH ON MINERALS IN POTATO CULTIVARS GROWN IN CANADA

• Many Canadians do not meet their dietary needs for magnesium, potassium, phosphorus, copper, iron, and zinc.

• Our lab at McGill University, with help from local industry, recently compared the mineral content of 16 cultivars grown at 5 sites in Canada.1

1Nassar et al. (2012) J Agric Food Chem 60:4688‐96

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MCGILL RECHERCHE SUR MINÉRAUX CHEZ LES CULTIVARS DE POMMES DE TERRE CULTIVÉES AU CANADA

MCGILL RESEARCH ON MINERALS IN POTATO CULTIVARS GROWN IN CANADA

• Across all 5 growing sites, ‘Russet Burbank’and ‘Yukon Gold’ had the greatest contribution of minerals per serving. 

• In one serving a day, these potatoes supply 

• 30‐62% of the RDI for magnesium, potassium, and phosphorus

• 12‐82% of the RDI of the trace minerals copper, iron, selenium, and zinc

• Potato makes a very important mineral contribution to the Canadian diet on a daily basis. 

• Canadians eat approx. 191 g/person/day; > one serving.

MCGILL RÉSULTATS DE L'ÉTUDE MINÉRALEMCGILL MINERAL STUDY OUTCOMES

• Industry could advertise the high mineral content of potato to promote specific high‐mineral cultivars to consumers.

• Potato is high in compounds that promote mineral bioavailability

• ascorbate, β‐carotene, organic acids, cysteine‐rich polypeptides.

• Potato is low in anti‐nutrients that decrease mineral bioavailability 

• oxalates, phytates

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VITAMINESVITAMINS

• Potatoes are one of the highest contributors of vitamin C to the diet in many parts of the world• single 148 g serving of baked potato provides approx. 45% of the recommended daily intake of vitamin C

• Vitamin C is important to availability of iron, which tends to be limiting in our diet.

• Provides significant amounts of several B vitamins (folic acid, niacin, pyridoxine, riboflavin, thiamin). Potatoes are a good dietary source of pyridoxine (vitamin B6).

RÔLE DE LA POMME DE TERRE DANS LE MAINTIEN DE LA SANTÉROLE OF POTATO IN MAINTAINING HEALTH

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RÔLE DE LA POMME DE TERRE DANS LA PRÉVENTION DES MALADIES

ROLE OF POTATO IN DISEASE PREVENTION

• Antioxidants are compounds that protect cells and tissues from the harmful effects of reactive free radical species.

• Consumption of foods high in antioxidant capacity improves antioxidant defenses in the body.

• Studies have repeatedly shown that people who eat more servings of fresh fruit and vegetables have reduced incidence of a wide range of metabolic diseases including cancer, heart disease, diabetes and neurodegenerative diseases.

RÔLE DE LA POMME DE TERRE DANS LE MAINTIEN DE LA SANTÉROLE OF POTATO IN MAINTAINING HEALTH

• Potato contain diverse antioxidants including

• Vitamin C

• Polyphenols• Anthocyanins ‐ Highly coloured potatoes are more widely grown in Canada now than in previous years. Some are for use in cooking or processed into chips.

• Phenolics ‐ Colorless compounds that are responsible for a large part of the antioxidant capacity of potato. These include chlorogenic acid, caffeic acid, ferulic acid, and others.

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POMME DE TERRE PEUT PRÉVENIR LES MALADIES MÉTABOLIQUES 

POTATO MAY PREVENT METABOLIC DISEASES

• Diabetes – this is an increasing problem world‐wide that is characterized by insulin resistance and often associated with obesity.

• Potatoes has readily absorbable carbohydrate that rapidly raises blood glucose but also contains anti‐diabetic factors such as polyphenols and minerals such as magnesium – complicates the role of potato in diabetes.

• Some polyphenols and magnesium can improve insulin sensitivity, which can be important in diabetes prevention.

VALEUR NUTRITIVE DES POMMES DE TERRE POTATO NUTRITIONAL VALUE

• There is no doubt that potato contributes to global health. The potato industry should confidently promote this healthy food.

Research and development are important to further optimize the nutritional characteristics of the potato:Increase resistant starch, protein, mineral content, diversity of vitamins, polyphenols, and other antioxidants (anthocyanins, carotenoids).

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REMERCIEMENTSACKNOWLEDGEMENTS

• This summary was prepared from the following sources:• Camire, M.E., S. Kubow and D.J. Donnelly. 2009 Potatoes and Human Health. Critical Reviews in Food Science and Nutrition. 49:823‐840.

• Nassar, A.M.K., K. Sabally, S. Kubow, Y.N. Leclerc and D.J. Donnelly. 2012. Some Canadian‐Grown Potato Cultivars Contribute a Substantial Content of Essential Dietary Minerals. Journal of Agricultural and food Chemistry. 60:4688‐4696.

• Reader, J. 2007. The Untold History of the Potato. Vintage Books. 315 p.

ACKNOWLEDGEMENTS

• Thanks are due to the following agencies for research support to our McGill team for studies on potato starch quality, mineral composition, and antioxidant capacity:

• NSERC Discovery Grants Program  (DJD, SK)

• NSERC Strategic Grants & Industry partners McCain Foods Canada, Province of NB, Wicklow Station (SK, DJD, and others.)

• MITACS Acceleration Québec, Internship support (AMKN and AE) 

• MAPAQ & Industry partners Fédération des Producteurs de Pommes de Terre du Québec, Patates Dolbec, Centre de Research Les Buissons, Association des Emballeurs de Pommes de terre du Québec (SK, DJD).